Modern sonar systems are built around the operation of transducers which are designed to both receive and transmit acoustical energy into the ocean environment. Typical high energy sonar transducers are composed of many individual acoustical transducer elements which are combined in arrays to maximize the power emission into an ocean environment as well as the reception of signals from the ocean environment.
Each transducer element in the array has its own characteristics for transforming acoustical energy into an electrical signal. In particular, the material of each transducer element may be characterized by a transconductance factor g which will very from element to element. A particular characteristic of the performance of transducer elements is contained in the product of g.times.L, where L is the thickness of the capacitative element of the piezoelectric transducer. If g were constant for the material used in all elements, the factor g.times.L could be maintained consistent by manufacturing all transducer elements to a common thickness L.
However, the effort required to ensure a consistent value for the transconductance g is too extensive, and therefore it becomes necessary to accept transducer elements with varying g.times.L factors. An alternative to the attempt at unifying the g.times.L factor during the manufacture of the product is to create a compensating device to be built in the sonar circuit which can compensate for variations in this factor during the receive mode. An effective compensation method of this type must not modify the transmit mode characteristics.